The mechanisms of actions of the anticancer drugs, pseudouridinedicarboxaldehyde (Psi-OX) and 2'-deoxyadenosine (dAdo) in combination with 2'-deoxycoformycin (dCF), will be studied as experimental therapeutic agents. The molecular sites of blockade will be investigated by biochemical oncological methodology and will include determination of enzymes inhibited and the Km/Ki ratios for these. In addition, Psi-OX inhibition of tubulin metabolism will be mechanistically studied. Limited murine survival studies will be employed to check hypotheses using the L1210 ascites tumor. The long term objectives of the research is to develop these drugs for clincial use in cancer chemotherapy.